'''
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Script to get NPM data via Modbus
need parameter: port
/usr/bin/python3 /var/www/nebuleair_pro_4g/NPM/old/test_modbus.py

Modbus RTU
[Slave Address][Function Code][Starting Address][Quantity of Registers][CRC]

Pour récupérer
 les concentrations en PM1, PM10 et PM2.5 (a partir du registre 0x38)
 les 5 cannaux
Donnée actualisée toutes les 10 secondes

Request
\x01\x03\x00\x38\x00\x55\...\...

\x01        Slave Address (slave device address)
\x03        Function code (read multiple holding registers)
\x00\x38    Starting Address (The request starts reading from holding register address x38 or 56)
\x00\x55    Quantity of Registers (Requests to read x55 or 85 consecutive registers starting from address 56)
\...\...    Cyclic Redundancy Check (checksum )

'''

import serial
import requests
import json
import sys
import crcmod
import sqlite3

# Connect to the SQLite database
conn = sqlite3.connect("/var/www/nebuleair_pro_4g/sqlite/sensors.db")
cursor = conn.cursor()

def load_config(config_file):
    try:
        with open(config_file, 'r') as file:
            config_data = json.load(file)
        return config_data
    except Exception as e:
        print(f"Error loading config file: {e}")
        return {}

# Load the configuration data
config_file = '/var/www/nebuleair_pro_4g/config.json'
config = load_config(config_file)
npm_solo_port = config.get('NPM_solo_port', '')  #port du NPM solo

ser = serial.Serial(
    port=npm_solo_port,
    baudrate=115200,
    parity=serial.PARITY_EVEN,
    stopbits=serial.STOPBITS_ONE,
    bytesize=serial.EIGHTBITS,
    timeout = 0.5
)

# Define Modbus CRC-16 function
crc16 = crcmod.predefined.mkPredefinedCrcFun('modbus')

# Request frame without CRC
data = b'\x01\x03\x00\x44\x00\x06'

# Calculate CRC
crc = crc16(data)
crc_low = crc & 0xFF
crc_high = (crc >> 8) & 0xFF

# Append CRC to the frame
request = data + bytes([crc_low, crc_high])
#print(f"Request frame: {request.hex()}")

ser.write(request)

while True:
    try:
        byte_data = ser.readline()
        formatted = ''.join(f'\\x{byte:02x}' for byte in byte_data)
        print(formatted)

        if len(byte_data) < 14:
            print(f"Error: Received {len(byte_data)} bytes, expected 14!")
            continue

        #10 secs concentration

        lsw_pm1 = int.from_bytes(byte_data[3:5], byteorder='big')  
        msw_pm1 = int.from_bytes(byte_data[5:7], byteorder='big') 
        raw_value_pm1 = (msw_pm1 << 16) | lsw_pm1
        raw_value_pm1 = raw_value_pm1 / 1000

        lsw_pm25 = int.from_bytes(byte_data[7:9], byteorder='big')  
        msw_pm25 = int.from_bytes(byte_data[9:11], byteorder='big') 
        raw_value_pm25 = (msw_pm25 << 16) | lsw_pm25
        raw_value_pm25 = raw_value_pm25 / 1000


        lsw_pm10 = int.from_bytes(byte_data[11:13], byteorder='big')  
        msw_pm10 = int.from_bytes(byte_data[13:15], byteorder='big') 
        raw_value_pm10 = (msw_pm10 << 16) | lsw_pm10
        raw_value_pm10 = raw_value_pm10 / 1000

        print("1 min")
        print(f"PM1: {raw_value_pm1}")
        print(f"PM2.5: {raw_value_pm25}")
        print(f"PM10: {raw_value_pm10}")

        break
    except KeyboardInterrupt:
        print("User interrupt encountered. Exiting...")
        time.sleep(3)
        exit()
    except:
        # for all other kinds of error, but not specifying which one
        print("Unknown error...")
        time.sleep(3)
        exit()

conn.close()